log periodic dipole antenna formulas

hi ! does anyone know any other formulas of an lpda regarding its length aside from L= 142.5/ f? tnx.....

Not sure how deep you want to dig in... but John Kraus Antennas, 2nd edition, McGraw-Hill, 1988 should be all what you need... but to get it a little simpler
ARRL Antenna handbook used to have a good source written by Pete Rhodes K4EWG.
From this you can down load a spread sheet to design your own antenna: http://www.cqham.ru/projects/logperio.xls

You find some information on this page too: W0RPK LPDA

Good Luck!

If you can find Smith's Log Periodic Design Handbook it should be helpful. It includes numerous examples.

Here's a great place to start: LPDA designs listing